To the best of our knowledge, only two compounds of formula (I) are known from the prior art. Said compounds are the 3-acetate of [1aR-(1aα,2β,3β,4aβ,8aS)]-decahydro-2,4a,8,8-tetramethyl-cyclopropa[d]naphthalene-2,3-diol, and the 2-acetate of (1aR,2S,3S,4aS,8aS)-decahydro-2,4a,8,8-tetramethyl-cyclopropa[d]naphthalene-2,3-diol which are reported as intermediate compounds in the oxidation of thujopsene (e.g. see G. Ohloff et al. in Helv. Chem. Acta 1970, 623 or G. Ohloff et al. in Recueil des Travaux Chimiques des Pays-Bas, 1974, 93, 264). However, none of the prior art documents mentions or suggests that said compounds can be used as perfuming ingredients. The other compounds of formula (I) are new.
The closest analog, which is reported in the prior art as a perfuming ingredient, is 4,7,11,11-tetramethyl-tricyclo[5.4.0.0(1,3)]undecan-5-one disclosed in U.S. Pat. No. 3,839,232. Said document does not suggest that the compounds of the present invention are also useful perfuming ingredients.